Infants who are fed peanut protein regularly have a lower risk of peanut allergy
A randomized controlled trial that included 640 infants younger than 11 months with either egg allergy or moderate–severe atopic dermatitis found that 3.2% of children in the treatment group, who ate 2 g of peanut butter 3 times per week, developed peanut allergy after 5 years compared with 17.2% of children in the avoidance group (p < 0.001).1
For most infants, peanut protein may be introduced at home between 4 and 6 months
To prevent the development of peanut allergy, it is sensible to introduce infant-safe peanut protein (i.e., paste, butter, powdered puff) as a first food. Information on the introduction of peanut is available in Canadian and American recommendations.2,3
Likelihood of peanut allergy is higher in infants with severe atopic dermatitis
The more severe the atopic dermatitis in infants, the greater the risk of peanut allergy, especially if other household members eat peanut at home.4 Infants without atopic dermatitis or with mild atopic dermatitis (e.g., requiring only barrier cream) are best suited for peanut introduction in the home.
Infants with risk factors for allergy should be seen by a specialist before introduction of peanut
The US National Institute of Allergy and Infectious Diseases recommends allergy testing (skin-prick or specific immunoglobulin E testing) in infants with severe eczema, egg allergy or both before introducing peanut.3 The Allergy Societies of Canada, Australia and the UK do not mandate this. Allergy tests for peanut can provide reassurance at negative or low values; universally agreed upon safe cut-off thresholds have not been established.4
Adequate amounts of peanut need to be eaten regularly to reduce the risk of allergy
Eight grams of peanut butter (1 heaped teaspoon, 1.5 regular teaspoon) or 17 g of peanut puffs should be consumed at least twice weekly to protect against peanut allergy.5 This intervention does not treat peanut allergy.
Acknowledgements
The authors thank Drs. Elissa M. Abrams and Edmond S. Chan for their helpful feedback on the manuscript.
Footnotes
CMAJ Podcasts: author interview at https://soundcloud.com/cmajpodcasts/181613-five
Competing interests: George du Toit has received grant and honoraria support from the National Institute of Allergy and Infectious Diseases ( NIAID, NIH), Food Allergy & Research Education (FARE), MRC & Asthma UK Centre, UK Department of Health through NIHR, Action Medical Research and the National Peanut Board. He sits on the Scientific Advisory Board of Aimmune Therapeutics and the HUK Advisory Board for DBV Technologies. He is the Principal Investigator on Aimmune and DB clinical trials. No other competing interests were declared.
This article has been peer reviewed.
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